The present invention relates to a fluidizable cracking catalyst composition comprising a zeolitic, crystalline aluminosilicate, a matrix material and a barium compound. A catalyst composition of this type is suitable for cracking oil feedstocks and is disclosed in U.S. Pat. No. 4,473,463. According to the description in that patent, barium compounds are incorporated into or applied onto cracking catalysts to prevent deleterious effects caused by metal contamination in oil feedstocks. The catalysts generally contain a silica-alumina matrix in which zeolitic materials are embedded. Preferably, use is made of barium acetyl acetonate. In this U.S. patent, the results obtained are described in an example in which a cracking catalyst contaminated with metals is re-activated in a treatment with barium acetyl acetonate. This compound, however, and many other barium compounds are not quite suitable to be used for composing a metal resistant cracking catalyst, as appears from metal resistance and micro-activity tests (referred to as MR test and MAT test, respectively).
A barium compound in which the cracking catalyst composition of the above well-known type but which contains a barium titanium oxide has now been found which does not show the above drawback.
Use of barium compounds in cracking catalysts is also known from other patent specifications. U.S. Pat. No. 4,179,409 describes a cracking catalyst which in addition to a zeolite and an inorganic oxide gel matrix contains a perovskite. As a result, the cracked oil will have a higher octane number. The perovskite may be a barium compound, such as barium zirconate (BaZrO.sub.3).
In the cracking process of EP 0 063 712, use is made of metal traps, such as type A zeolite, which may contain for instance a barium compound. It should be added that U.S. Pat. No. 4,451,355 relates to a cracking catalyst which in addition to a zeolite aluminosilicate and a matrix material contains a calcium-containing additive for trapping metal contaminations. Particular calcium/titanium-containing compounds, including calcium titanate (CaTiO.sub.3), are considered to be particularly suitable for this purpose.